Embattled city Comptroller John Liu last night all but declared he’ll run for mayor next year, despite a criminal probe of his campaign finances, telling supporters, “I’m going all the way!”

Liu’s fiery words — delivered at a rally on his behalf in Harlem — came just hours before his ex-campaign treasurer Jenny Hou was to be arraigned in Manhattan federal court this morning on charges of lying to the FBI and scheming to funnel illegal donations to his campaign.

But Liu appeared buoyed after hearing a dozen faith-based leaders defend his honor at Mother AME Church — with a few even saying he’s been unfairly persecuted and likening his plight to Jesus Christ.

“Keep going John,” the pro-Liu crowd of some 300 people, including many union members, chanted.

“I absolutely will,” Liu responded. “I have a new nickname: the embattled comptroller. Well, I’m willing, ready and able to do battle for the City of New York.”

Liu’s handlers billed the rally as just an outlet for allies to express their backing.

But Liu suggested in no uncertain terms, he’s preparing for a run

“I’m going to keep going. I’m going to go all the way!” Liu declared.

Liu also sent prosecutors a message by presenting a united front with Hou.

Hou’s lawyer, Gerald Lefcourt, also addressed Liu supporters and vowed his client will fight the federal charges — not cut a deal with prosecutors or turn on Liu.

“Jenny will not only plead not guilty. She is not guilty. Free Jenny!” Lefcourt said.

He even made a pitch for folks to contribute to Hou’s legal defense fund.

For his part, Liu got emotional when discussing Hou, 25, a native of Beijing who started out as a volunteer on his successful 2009 bid for comptroller.